Direction signaling system



July 8, 1952 J. w. LAWSON ET AL DIRECTION SIGNALING SYSTEM 4 Sheets-Sheet 1 Filed July '22, 1948 ,0 f Mp July 8, 1952 J. w. LAWSON ETAL DIRECTION SIGNALING SYSTEM 4 Sheets-Sheet 2 Filed July 22, 1948 INVENggm July 8, 1952 J. W. LAWSON ETAL DIRECTION SIGNALING SYSTEM 4 Sheets-Sheet 3 Filed July 22, 1948 y 8, 1952 J. w. LAWSON ETAL 2,602,849

DIRECTION SIGNALING SYSTEM Filed July 22, 1948 4 Sheets-Sheet 4 Patented July 8, 1952 DIRECTION- SIGNAEING SYSTEM- John W. Lawson and William E. Brown,.Anderson, Ind., assignors to General Motors Corporation, Detroit, Mich, a. corporation of Delaware Application July 22, 1948;.Serial No. 40,196

This invention relates to systems of direction and stop signalling for automotive use.

An object of the invention is to provide a turn signal switch of simple economical and durable construction by which current is directed to the signal lamps which indicate direction of turn and stopping when brakes are applied. This object is accomplished in the disclosed embodiment of the invention by the provision of two rowsv of stationary contacts of three contacts each. The center contact of the first row is connected with the current source through a stop switch which is closed whenthe brakes are applied and the end contacts of the first row are connected re-- spectively with right-rear and left-rear lamps. The center contact of the second row is connected with the source through a-fiasher and the end contacts of the secondrow are connected respectively with the right-front and left-front turn-signal lamps. The switch provides three movable contacts which ar simultaneously actuated. One of the movable contacts has a center position connecting all contacts of the first row and has positions on either side of center position for connecting thecenter contact of the first row with one or the other of the end'contacts of the firstrow. Thus the'stop light switch will cause both of the rear lamps to burn in case the turn signal switch is in no-turn or neutral status, and will cause one or the other of the rear lamps to burn steadily in case the turn signal switch is manipulated to indicatev a turn. Whenthe turn signal switch is manipulated to indicate a right turn, another movable contact connects the stationary center contact of the second row with those end contacts of the two rows which are connected respectively with right front and right rear lamps which burn intermittently.

When the turn signal switch is manipulated to indicate a left turn, another movable contact connects the stationary second contact of the second row with those end contacts of the'two rows which are connected respectively with the left-front and left-rear lamps which burn intermittently.

The first mentioned movable contact has five contact bosses. The non-conducting stationary contact support provides recesses around the contacts of the firstrow so that the nonfunctioning contact bosses of the first mentioned. movable contact will not engage a stationary'piartandwill not therefore, interfere with proper engagement with stationary contacts by the functioning. contact bosses. The first mentioned movable-contact makeseither three-point (tripod) ortwo- 9' Claims. (Cl. 177-337) point engagement with stationary contacts. Each of the other movable contacts has three contact bossesand-can make by virtue of threepoint contactthe proper electrical connection with three stationary contacts.

Another object is to facilitate the control of pilot lamps which indicate the functioning. of the systems For this purpose, each end contact of the second mentioned row of fixed contacts is connected also with a pilot lamp. The two pilot lamps are connected with the current source by a relay switch associated with the flasher. When manipulated to indicate aturn, the turn-signal switch shorts out one of the pilot lamps while the other pilot lamp burns, its circuit being. made through that front turn-signal lamp which is not then incircuit with the flasher.

Further objects and advantagesof the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred-embodiment of the invention is'clearly shown.

In the drawings:

Fig. 1. is a wiringdiagram of a directional signal light. and stop light system embodying the present invention.

Figs. 2 and 3 show the system under difierent operating conditions.

- Fig; 4 is abottom view of a switch included in the system shown in Fig. l. V

Fig. 5 is aview in the direction of arrow 50f Fig. 4, certain parts being shown in section.

Fig. 6 shows the switch case in section on line 6-6' of Fig. 5 and a bottom plan view of the movable contacts of the switch.

Fig. 7 is a sectional view on line 1 of Figs- 4, 5,16 and 9.

Fig. 8 is a sectional view on line 8-8 of Figs. l -and 6.

Fig. 9 shows atop plan view of the carrier of the movable contacts of the switch, the casebeing in section on line 9-9 of Fig. 5.

Fig. 10 isa plan view of a switch housing and switch operating mechanism.

Fig. 11 is a fragmentary view similar. to Fig- 10, certain parts being removed in order to show the switch-case in position in the'housing.

Figs. 12and 13 are sectional views on lines l2--l2- and l3 -l3 respectively of Fig. 10.

Figs. 14,. 15 and 16 are inside views of: the Switchback plate 26' with the movable contacts shown in different positions in these views.

, T-heswitch case 20 shaped like an arcuate channel and is provided with mounting brackets 2| and 2-2. Its concentric cylindrical side walls 3 23 and 24 merge with an arcuate, flat wall 25. As shown in Fig. 11, wall 25 is the top wall. The

case 29 is closed at the bottom (top in Fig. 4) by a non-conducting back plate 29 having notches 21 for receiving tangs extending from the side walls of the case, said tangs being bent over at 28 into recess 29 provided by the plate. The plate carries members 33, 3|, 32, 33, 34 and 35 which serve as terminals and also as stationary contact members, said members being inserts (as shown in Fig. 8) in plate 25 which is made of molded insulating material. Case 29 encloses a movable contact carrier 3'! of arcuate. shape as shown in Fig. 6 which is movable in an arcuate' path between the case walls 23 and 24 and is guided for such movement by a plurality of balls 38 received respectively by recesses 39 of the" carrier 3! and bearing against the corner portions of the case 29. Contact springs 49 which urge movable contacts -I9, I9 and 89 (Fig. 6) toward the plate 26 maintain the carrier 31 in contact with balls 38 and the latter in contact with the walls of the switch case as shown in Fig. '7.

Carrier 31 provides a cylindrical-lug M which extends through an arcuate slot 42 of case wall 25 and through a radial slot43 of a ring plate 44 supported by housing 45 for rotation coaxially thereof. Housing 45 is adapted to be mounted upon the stationary steering column post of an automobile and to be located under the steering wheel so that a handle 96 attached to the plate 44 is readily accessible to the driver. 'HOu'sing 45 is provided with tracks 41 for receiving balls 48 which are received by tracks provided by clips Hand 59 attached to the plate 44, clip 49 being relatively rigid and clip 59 relatively resilient.

Plate 44 is retained in neutral position shown in Fig. 19 by the cooperation of a detent clip 5| attached to housing 45 with a roller 52 and a stud 53 pivotally attached to plate '44. Switch case bracket 2| is attached by a screw 2la to housing 45 and switch case bracket '22-is attached by a screw 22a. Bracket 22 provides pivots 55 for arms 54 carrying studs 59 supporting rollers 5'! a lever 69 pivotally supported by a stud 5|.

When handle 49 is moved down in Fig. 19 to rotate plate 44 clockwise, the surface 59a of lever 99 is brought into contact with the upper roller 51 which biases the lever 99 toward a cam rotating with the steering wheel shaft (not shown). Similarly when handle 46 is moved up and plate 44 is moved counterclockwise, the portion 69b of lever 69 is engaged by the lower roller 51, thereby biasing it toward the steering wheel cam.

In advance of making a right turn, the handle 46 is moved down to cause lever 69 to be urged clockwise so that its upper portion will be engaged by a cam rotatable with the steering wheel shaft. Consequently when the steering-wheel is turned clockwise to make a right turn, the tendency is to maintain the plate 44 in the position in which it had been moved by the handle 46. After the turn has been partially completed and the driver reverses motion of the steering wheel to straighten out the front wheels of the automobile, this reverse motion of the steering wheel through mechanical connection with the end of lever 89 causes plate 44 to move back to neutral position, thereby interrupting the signal for the right-hand turn. The same thing happens with respect to the left-hand turn. The mechanism for accomplishing this is not per se a part of the present invention.

Referring again to Figs. 4 to 8, the contact carrier 31 supports a movable contact I9 having five contact bosses II, I2, I3, I4, I5, a contact I5 having bosses TI, I8 and I9 and a contact 89 having bosses 8|, 82 and 93. Between the carrier 37 and each of the bosses of the contacts I5 and 89 there is located a spring 49 as shown in Fig. I.

' Between the carrier 31 and each of the bosses II,

neutral position.

I3 and I5 there is located a spring 49 as shown in Fig. 8.

Fig. 1 shows the movable contacts I6 and 89 in Contacts 39 and 32 are not connected with the contact 3I. Contact I9 conn-ects contacts 33, 34- and 35. When the stop light switch 99 is closed, current flows from the battery 9| to the right rear lamp 92 and the left rear-lamp 93 to indicate application of brakes.

- When lever 49 (Fig. 19) is moved counterclockwise the contacts I9, I9 and 89 move to the position shown in Fig. 2. Current then flows from battery 9| to flasher terminal 94, hinged blade 95, hot wire 99, resistor 91, contact 98 (normally separated from contact 99 carried by blade magnet coil I99, terminal I9I, wire I92, contact 3|, contact 89, contact 39, wire I93, lamp I94 and also through contact 89, contact 33 and wire I95 to left rear lamp 93. Current flowing in wire 95 causes it toexpand to permit blade 95 to bias downwardly to move its contact 99 into engagement with contact 98, thereby short-circuiting resistor 91 and hot wire 96. The temperature of "wire 96 decreases and it contracts to pull contact 99 away from contact 99, thereby interrupting the short-circuit of wires 95 and 9! whereupon current again flows to heat wire 99 and contact 99 eturns into'engagement with contact 98. This cycle isrepeatedso long as contact 89 remains I in the position shown. Therefore the lamps I94 and 93burn intermittently to'indicate by a flashing signal a left turn.- At the same time a hinged armature blade I99 is attracted to move its contact I91 into engagement with a contact I99. This connects the battery with left turn pilot lamp I99 and right turn pilot lamp H9. Lamp I99 burns because its circuit is completed through right front lamp I I I which does not burn perceptibly because the voltage drop through it is insufficient.. 'If the brakes are applied, switch 99 is closed and, lamp 92 burns steadily to indicate a stop, while lamp 93 burns intermittently to indicate a turn.

i Fig. 3 shows the positions of the switch contacts I9; I9 and 89 when handle 49 has been moved down (Fig. 10) to indicate a right turn. Since contact I9 connects contacts 3I, 32 and 35. right front signal lamp I I I and right rear signal lamp 92 burn intermittently through the operation of the flasher in the manner described with reference toFig. 2; Blade I99 moves up as be- ,foreto'connect contacts I91 and I 98 and pilot lamp I. I9 indicates that the flasher is operating the rightturn signals, the circuit of lamp IIIJ beingcompleted through lamp I94 which does notburn perceptibly. Pilot lamp I99 does not burn. since it is short-circuited by the circuit through magnet coil I99 andwire I92. When brakes'are applied stop. light switch 99 is closed and left rear lamp 93 burns steadily to indicate the applicationofbrakes. while, lamp 92 is flashing to indicate a right turn.

From the foregoing it is apparent that the system provides for the indication of turns by the flashing of the proper front and rear lamps, for the steady burning of the non-flashing rear-lamp when. brakes are applied and for the indication by pilotilamps that the'system is operating properly for'left and right turns. If, when the system is set. for indicating a left turn, pilot. lamp. I09 does not burn, this is anindication that the si na'l'system is not. operatingproperly; and, when right turn pilot lamp I I does not burn when the switch is set for right turn signal, this is anindication that the system is not operating properly.

Referring to Figs. 14, 1'5 and 16, it will be noted that the switch back plate 26 is provided with recess. d adjoining the heads of contact members 33, 34 and 35. In the neutral position of the switch, bosses H, 13 and'l5 engage contacts 33, and .35, respectively, and bosses I2 and I4 face into the recess d and do not touch anything. Since bosses H, 13 and 15 are not on the same line, they make a tripod or three-point contact with contacts 33, 3-! and 35. In other positions of contact as shown in Figs. and 16, a twopoint contact is made with stationary contacts. Ihe other movable contacts have three bosses each so that they will make a tripod or threepoint contact respectively with contacts 3|, 32,

35. and contacts 39, 3|, 33. Although contact Hi While the embodiment of the present invention I as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. In a direction signalling system for vehicles including right front, left front, right rear and left rear indicating lamps, turn signal switching means, circuits connecting each of said lamps to said switching means, a source of current for said lamps, an electrically-operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said Q switch, means provided in said switching means for selectively connecting the right front and right rear lamps or the left front and left rear lamps to said source through said flasher switch,

a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal connected to said source, and a pair of pilot lamps connected in parallel circuits between the front lamps and the output terminal of said interrupter.

2. In a direction signalling system for vehicles including right front, left front, right rear and left rear indicating lamps, turn signal switching means, circuits connecting each of said lamps to said switching means, a source of current for said lamps, an electrically-operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switch, means provided in said switching means for selectively connecting the right front and right rear lamps or the left front and left rear lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating 6. mechanism of said flasher switch, and a-pair of pilot lamps connectedi-n parallel circuits between the output terminal ofsaid interrupter and the circuits between the front lamps and said switching means.

'3. In a direction signalling system for vehicles including right front, left front, right; rear and left rear indicating lamps, turn signal switching means, circuits connecting each of said lamps-to saidswitching means, a source of current for said lamps, an electrically-operated automatic flasher switch having its intermittent-contact actuating mechanism connected in a series circuit between said source and said switchin means for periodically interrupting the current flow to said switch, means provided insaid switch ing means for selectively connecting the right front and right rear lamp or the left front and left rear lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal-connected to said source and its output terminal connected by parallel circuits to each of said front lamps and a pilot lamp connected in series in each of said parallel circuits.

4. In a direction signalling system for vehicles including right front, left front, right rear and left rear indicating lamps, turn signal switching means, circuits connecting each of said lamps to said switching means, a source of current for energizing said lamps, an electrically-operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switch, means provided in said switching means for selectively connecting either, the right front and right rear lamps or the left front and left-rear lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch having its input terminal connected to said source and its output terminal connected to the terminals of a pair of pilot lamps, parallel circuits connecting the other terminals of the pilot lamps to the respective front lamps, one or the other of said pilot lamps being energized through the non-signaling front lamp circuit when the other front and corresponding rear lamp circuits are connected to said source for intermittent energization through said flasher switch.

5. In a direction signalling system for vehicles including a right front lamp, a right rear lamp, a left front lamp, a left rear lamp and a pair of pilot lamps, turn signal switching means, circuits connecting each of said front and rear lamps to said switching means, a source of current for energizing said lamps, an electrically operated flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switch, means provided in said switching means for selectively connecting either the right front and right rear lamps or the left front and left rear lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch having its input terminal connected to said source and its output terminal connected to the terminals of said pilot lamps, parallel circuits connecting the other terminals of said pilot lamp respectively to each of said front lamps for intermittent energization of one or the other of said pilot lamps through its circuit to the front lamp disconnected by said switching means from energization from said source through said flasher switch when the other front lamp and corresponding rear lamp circuits are connected by said switching'means to said source for intermittent energization through said flasher switch. v I

6.In a direction signaling system for vehicles includingv left and right front signaling lamps, direction signal switching means, circuits connecting each of .said lamps to said switching means, a source of current for said lamps, an electrically operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switching means, means provided in said switching means for selectively connecting said signaling lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal connected to said source and a pair of pilot lamps connected in parallel circuits between said signaling lamps and the output terminal of said interrupter.

7. In a direction signaling system for vehicles including left and right signaling lamps, direction signal switching means, circuits connecting each of said lamps to said switching means, a source of current for said lamps, an electrically operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said-source and said switching means for periodically interrupting the current flow to said switching means, means provided in said switching means for selectively connecting said signaling lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal connected to said source anda pair of pilot lamps connected in parallel circuits between said signaling lamps and the output terminal of said interrupter.

8. In a direction signaling system for vehicles including left and right rear signaling lamps, direction signal switching means, circuits connecting each of said lamps to said switching means, a source of current for said lamps, an electrically operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switching means, means provided in said switching means for selectively connecting said signaling lamps ,to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal connected to said source and a pair of pilot lamps connected in parallel circuits between said signaling lamps and the output terminal of said interrupter.

9. In a direction signaling'system for vehicles including. left and right rear signaling lamps, direction signal switching means, circuits connecting each of said lamps to said switching means, a source of current for said lamps, an electrically operated automatic flasher switch having its intermittent contact actuating mechanism connected in series circuit between said source and said switching means for periodically interrupting the current flow to said switching means, means provided in said switching means for selectively connecting said signaling lamps to said source through said flasher switch, a circuit interrupter actuated by the contact actuating mechanism of said flasher switch, said interrupter having its input terminal connected to said source, a pair of pilot lamps connected in parallel circuits between said signaling lamps and the output terminal of said interrupter, and means including a brake operable switch in the circuit between said source of current and said direction signal switching means for causing energization of both of said signaling lamps when neither is caused to be energized by said direction signal switching means, causing steady energization of the left signaling lamp when the right signaling lamp is caused to be energized by said direction signal switching means, and steady energization of said right signaling lamp when the left signaling lamp is caused to be energized by said direction signalling switching means.

JOHN W. LAWSON. WILLIAM E. BROWN.

REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS Hollins Nov. 1, 1949 

